SO逆向入门实战教程六：s

Posted 2021-09-07 Gendan

package com.lession6;
import java.nio.charset.StandardCharsets;
import java.util.Map;
import java.util.SortedMap;
import java.util.TreeMap;
public class utils {

private static final char[] f14934c = "0123456789ABCDEF".toCharArray();
public static final String KEY_VALUE_DELIMITER = "=";
public static final String FIELD_DELIMITER = "&";
private static boolean a(char c2, String str) {
    return (c2 >= \'A\' && c2 <= \'Z\') || (c2 >= \'a\' && c2 <= \'z\') || !((c2 < \'0\' || c2 > \'9\') && "-_.~".indexOf(c2) == -1 && (str == null || str.indexOf(c2) == -1));
}
static String r(Map<String, String> map) {
    String str;
    if (!(map instanceof SortedMap)) {
        map = new TreeMap(map);
    }
    StringBuilder sb = new StringBuilder(256);
    for (Map.Entry<String, String> entry : map.entrySet()) {
        String key = entry.getKey();
        if (!key.isEmpty()) {
            sb.append(b(key));
            sb.append(KEY_VALUE_DELIMITER);
            String value = entry.getValue();
            if (value == null) {
                str = "";
            } else {
                str = b(value);
            }
            sb.append(str);
            sb.append(FIELD_DELIMITER);
        }
    }
    int length = sb.length();
    if (length > 0) {
        sb.deleteCharAt(length - 1);
    }
    if (length == 0) {
        return null;
    }
    return sb.toString();
}
static String b(String str) {
    return c(str, null);
}
static String c(String str, String str2) {
    StringBuilder sb = null;
    if (str == null) {
        return null;
    }
    int length = str.length();
    int i2 = 0;
    while (i2 < length) {
        int i3 = i2;
        while (i3 [期货](https://www.gendan5.com/futures.html)< length && a(str.charAt(i3), str2)) {
            i3++;
        }
        if (i3 != length) {
            if (sb == null) {
                sb = new StringBuilder();
            }
            if (i3 > i2) {
                sb.append((CharSequence) str, i2, i3);
            }
            i2 = i3 + 1;
            while (i2 < length && !a(str.charAt(i2), str2)) {
                i2++;
            }
            byte[] bytes = str.substring(i3, i2).getBytes(StandardCharsets.UTF_8);
            int length2 = bytes.length;
            for (int i4 = 0; i4 < length2; i4++) {
                sb.append(\'%\');
                sb.append(f14934c[(bytes[i4] & 240) >> 4]);
                sb.append(f14934c[bytes[i4] & 15]);
            }
        } else if (i2 == 0) {
            return str;
        } else {
            sb.append((CharSequence) str, i2, length);
            return sb.toString();
        }
    }
    return sb == null ? str : sb.toString();
}

}
补其实现

@Override
public DvmObject<?> callStaticObjectMethod(BaseVM vm, DvmClass dvmClass, String signature, VarArg varArg) {
    switch (signature){
        case "com/bilibili/nativelibrary/SignedQuery->r(Ljava/util/Map;)Ljava/lang/String;":{
            DvmObject<?> mapObject = varArg.getObjectArg(0);
            TreeMap<String, String> mymap = (TreeMap<String, String>) mapObject.getValue();
            String result = utils.r(mymap);
            return new StringObject(vm, result);
        }
    }
    return super.callStaticObjectMethod(vm, dvmClass, signature, varArg);
}